U.S. patent number 8,283,821 [Application Number 12/639,267] was granted by the patent office on 2012-10-09 for superconducting apparatus.
This patent grant is currently assigned to Aisin Seiki Kabushiki Kaisha, Toyota Jidosha Kabushiki Kaisha. Invention is credited to Hidetoshi Kusumi, Yoshimasa Ohashi, Nobuo Okumura.
United States Patent |
8,283,821 |
Ohashi , et al. |
October 9, 2012 |
Superconducting apparatus
Abstract
A superconducting apparatus includes a magnetic field generating
portion including a superconducting coil, an extremely low
temperature generating portion maintaining the superconducting coil
at an extremely low temperature and in a superconducting state, a
container defining a heat insulation chamber that accommodates the
superconducting coil, a first terminal electrically connected to
the superconducting coil and supplying an electric power to the
superconducting coil, a second terminal connected to an external
electric power source and supplying the electric power to the first
terminal in a case where the magnetic field generating portion is
driven, and a heat penetration preventing element holding one of
the first and second terminals and thermally separating the first
and second terminals from each other in a case where a driving of
the magnetic field generating portion is stopped, the heat
penetration preventing element restraining a heat penetration from
the second terminal to the first terminal.
Inventors: |
Ohashi; Yoshimasa (Kariya,
JP), Okumura; Nobuo (Toyota, JP), Kusumi;
Hidetoshi (Nagoya, JP) |
Assignee: |
Aisin Seiki Kabushiki Kaisha
(Kariya-shi, JP)
Toyota Jidosha Kabushiki Kaisha (Toyota-shi,
JP)
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Family
ID: |
42221077 |
Appl.
No.: |
12/639,267 |
Filed: |
December 16, 2009 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20100148894 A1 |
Jun 17, 2010 |
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Foreign Application Priority Data
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Dec 17, 2008 [JP] |
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2008-320755 |
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Current U.S.
Class: |
310/71; 310/89;
335/216 |
Current CPC
Class: |
H02K
55/02 (20130101); H02K 9/20 (20130101); Y02E
40/622 (20130101); H01F 6/00 (20130101); Y02E
40/60 (20130101); H02K 5/225 (20130101) |
Current International
Class: |
H02K
11/00 (20060101) |
Field of
Search: |
;310/71,89 ;335/216 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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2006-238570 |
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Sep 2006 |
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JP |
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2007-89345 |
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Apr 2007 |
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JP |
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WO 2006067915 |
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Jun 2006 |
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WO |
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Primary Examiner: Leung; Quyen
Assistant Examiner: Pham; Leda
Attorney, Agent or Firm: Oblon, Spivak, McClelland, Maier
& Neustadt, L.L.P.
Claims
The invention claimed is:
1. A superconducting apparatus, comprising: a magnetic field
generating portion including a superconducting coil that generates
a magnetic flux; an extremely low temperature generating portion
maintaining the superconducting coil at an extremely low
temperature and maintaining the superconducting coil in a
superconducting state; a container defining a heat insulation
chamber that accommodates the superconducting coil; a first
terminal electrically connected to the superconducting coil and
supplying an electric power to the superconducting coil; a second
terminal connected to an external electric power source and
supplying the electric power to the first terminal in a case where
the magnetic field generating portion is driven; and a heat
penetration preventing element holding one of the first and second
terminals and thermally separating the first and second terminals
from each other in a case where a driving of the magnetic field
generating portion is stopped, the heat penetration preventing
element restraining a heat penetration from the second terminal to
the first terminal, wherein the container includes a first holding
portion holding the first terminal and the heat penetration
preventing element includes a second holding portion holding the
second terminal and a distance adjusting portion adjusting a
distance between the first holding portion and the second holding
portion, the distance adjusting portion separating the first
holding portion and the second holding portion from each other to
mechanically separate the second terminal held by the second
holding portion from the first terminal held by the first holding
portion, the first terminal and the second terminal being thermally
separated from each other.
2. The superconducting apparatus according to claim 1, wherein the
magnetic field generating portion includes a superconducting motor
having a stator and a mover which is movable relative to the
stator, and the superconducting coil is provided at one of the
stator and the mover.
3. The superconducting apparatus according to claim 1, wherein the
heat insulation chamber of the container includes a vacuum heat
insulation chamber, and the heat penetration preventing element is
maintained in a vacuum heat insulation state while being connected
to the vacuum heat insulation chamber, the heat penetration
preventing element including a thermally insulated chamber having a
hollow shape in which the first terminal and the second terminal
are electrically connected to each other in a case where the
magnetic field generating portion is driven.
4. The superconducting apparatus according to claim 1, wherein one
of the first and second terminals includes a female portion and the
other one of the first and second terminals includes a male portion
engageable with the female portion.
5. The superconducting apparatus according to claim 4, further
comprising an elastic member disposed between the female portion
and the male portion and being elastically deformable, the elastic
member being formed by a conductive material to improve an electric
contact between the female portion and the male portion.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
This application is based on and claims priority under 35 U.S.C.
.sctn.119 to Japanese Patent Application 2008-320755, filed on Dec.
17, 2008, the entire content of which is incorporated herein by
reference.
TECHNICAL FIELD
This disclosure relates to a superconducting apparatus including a
superconducting coil.
BACKGROUND DISCUSSION
A known superconducting apparatus is disclosed in JP2006-238570A
(which will be hereinafter referred to as Reference 1). The
superconducting apparatus disclosed in Reference 1 includes a rotor
on which a superconducting coil is mounted. The rotor is arranged
within a heat insulation container of which a bottom portion is
filled with liquid nitrogen serving as a refrigerant. According to
the superconducting apparatus disclosed in Reference 1, a lower
portion of the rotor is immersed in the refrigerant so that the
refrigerant disperses within the heat insulation container by means
of a rotation of the rotor.
In addition, another known superconducting apparatus is disclosed
in JP2007-89345A (which will be hereinafter referred to as
Reference 2). The superconducting apparatus disclosed in Reference
2 includes a conductive cooling mechanism that is maintained at an
extremely low temperature by a refrigerator. A superconducting coil
mounted on a stator is cooled through a conductive cooling by the
conductive cooling mechanism.
According to each of the aforementioned superconducting apparatuses
disclosed in References 1 and 2, an external heat may be
transmitted to the superconducting coil via a feed terminal in a
case where a driving of the superconducting apparatus is stopped,
which may lead to a temperature increase of the superconducting
coil.
A need thus exists for a superconducting apparatus which is not
susceptible to the drawback mentioned above
SUMMARY
According to an aspect of this disclosure, a superconducting
apparatus includes a magnetic field generating portion including a
superconducting coil that generates a magnetic flux, an extremely
low temperature generating portion maintaining the superconducting
coil at an extremely low temperature and maintaining the
superconducting coil in a superconducting state, a container
defining a heat insulation chamber that accommodates the
superconducting coil, a first terminal electrically connected to
the superconducting coil and supplying an electric power to the
superconducting coil, a second terminal connected to an external
electric power source and supplying the electric power to the first
terminal in a case where the magnetic field generating portion is
driven, and a heat penetration preventing element holding one of
the first and second terminals and thermally separating the first
and second terminals from each other in a case where a driving of
the magnetic field generating portion is stopped, the heat
penetration preventing element restraining a heat penetration from
the second terminal to the first terminal.
According to another aspect of this disclosure, a movable
connecting device for selectively establishing and interrupting an
electrical connection between an electric power source and a
superconducting apparatus, the movable connecting device includes a
movable member, a thermally insulated chamber provided between the
superconducting apparatus and the movable member, first plural
terminals extending from the superconducting apparatus into the
thermally insulated chamber, second plural terminals extending from
the electric power source into the thermally insulated chamber, and
a driving device moving the movable member in first and second
directions, to establish connecting and disconnecting conditions
between the first plural terminals and the second plural terminals,
when the superconducting apparatus is in operation and out of
operation, respectively.
BRIEF DESCRIPTION OF THE DRAWINGS
The foregoing and additional features and characteristics of this
disclosure will become more apparent from the following detailed
description considered with the reference to the accompanying
drawings, wherein:
FIG. 1 is a cross-sectional view of a superconducting motor device
according to a first embodiment disclosed here;
FIG. 2 is a cross-sectional view illustrating a state where feed
terminals and current lead-in terminals are thermally disconnected
from each other according to the first embodiment;
FIG. 3 is a cross-sectional view illustrating a state where the
feed terminals and the current lead-in terminals are thermally
connected to each other according to the first embodiment;
FIG. 4 is a cross-sectional view illustrating a state where the
feed terminals and the current lead-in terminals are thermally
disconnected from each other according to a second embodiment
disclosed here;
FIG. 5 is a cross-sectional view illustrating a state where the
feed terminals and the current lead-in terminals are thermally
connected to each other according to the second embodiment;
FIG. 6 is a cross-sectional view illustrating a state where the
feed terminals and the current lead-in terminals are thermally
disconnected from each other according to a third embodiment
disclosed here;
FIG. 7 is a cross-sectional view illustrating a state where the
feed terminals and the current lead-in terminals are thermally
disconnected from each other according to a fourth embodiment
disclosed here;
FIG. 8 is a cross-sectional view illustrating a state where the
feed terminals and the current lead-in terminals are thermally
disconnected from each other according to a fifth embodiment
disclosed here;
FIG. 9 is a cross-sectional view illustrating a state where the
feed terminals and the current lead-in terminals are thermally
disconnected from each other according to a sixth embodiment
disclosed here;
FIG. 10 is a cross-sectional view of the superconducting motor
device according to a seventh embodiment disclosed here; and
FIG. 11 is a cross-sectional view of the superconducting motor
device according to an eighth embodiment disclosed here.
DETAILED DESCRIPTION
A first embodiment disclosed here will be explained with reference
to FIGS. 1 to 3. The present embodiment is applied to a
superconducting motor device 1, which is an example of a magnetic
field generator serving as a representative example of a
superconducting apparatus. The superconducting motor device 1 may
be used in a vehicle, in a stationary state, for an industrial
purpose, and the like. The superconducting motor device 1 includes
a superconducting motor 2 serving as a magnetic field generating
portion, an extremely low temperature generating portion 3, a
container 4, electric current lead-in terminals 5 (hereinafter
simply referred to as lead-in terminals 5) serving as first
terminals, and feed terminals 6 serving as second terminals.
The superconducting motor 2 serves as a motor to which a
three-phase alternating current is supplied. The three phases are
different from one another by 120 degrees each. The superconducting
motor 2 includes a stator 20 having a cylindrical shape around an
axial center P1 of the superconducting motor 2 and a rotor 27
serving as a mover rotating relative to the stator 20. The rotor 27
includes a rotational shaft 28 rotatably supported about the axial
center P1 of the superconducting motor 2 and multiple permanent
magnet portions 29 arranged at equal intervals at an outer
peripheral portion of the rotational shaft 28. The permanent magnet
portions 29 are formed by known permanent magnets.
The stator 20 includes a stator core 21 and a superconducting coil
22. The stator core 21 is formed into a cylindrical shape by a
material having a high magnetic permeability serving as a permeable
core. The superconducting coil 22 is wound on the stator core 21
and held thereat. The superconducting coil 22 is divided into three
portions so that the three-phase alternating current can be
supplied. The superconducting coil 22 is formed by a known
superconducting material. The superconducting coil 22 is arranged
within throttle grooves 21a formed at an inner peripheral portion
of the stator core 21. In a case where the three-phase alternating
current is supplied to the superconducting coil 22, a rotational
magnetic field is generated, rotating around the stator 20, i.e.,
the axial center P1 of the stator 20. The rotor 27 rotates about
the axial center P1 by means of the rotational magnetic field,
thereby obtaining a motor function.
The extremely low temperature generating portion 3 maintains the
superconducting coil 22 at an extremely low temperature so as to
retain a superconducting state of the superconducting coil 22. An
extremely low temperature range obtained by the extremely low
temperature generating portion 3 is selected depending on a
material of the superconducting material that constitutes the
superconducting coil 22. The temperature range may be equal to or
smaller than a helium liquefaction temperature or equal to or
smaller than a nitrogen liquefaction temperature. For example, the
temperature range is equal to 0 to 150K, specifically, 1 to 100K or
1 to 80K. At this time, however, the temperature range is not
limited to such values and is dependent on the superconducting
material forming the superconducting coil 22. The extremely low
temperature generating portion 3 includes a refrigerator 30 having
a cold head 32 where the extremely low temperature is generated,
and a conductive portion 33 having a temperature conductive
material as a base material for connecting the cold head 32 of the
refrigerator 30 to the stator core 21 of the stator 20 of the
superconducting motor 2. A known refrigerator such as a pulse tube
refrigerator, Stirling refrigerator, Gifford-McMahon refrigerator,
Solvay refrigerator, and Vuilleumier refrigerator is used as the
refrigerator 30. The conductive portion 33 is made of a material
having a temperature conductivity such as copper, copper alloy,
aluminum, and aluminum alloy.
As illustrated in FIG. 1, the container 4 includes a vacuum heat
insulation chamber 40 serving as a decompressed heat insulation
chamber for heat-insulating the superconducting coil 22. At this
time, the term "vacuum" corresponds to a decompressed state in
which heat insulation is achieved. The vacuum heat insulation
chamber 40 of the container 4 includes an outer vacuum heat
insulation chamber 41 and an inner vacuum heat insulation chamber
42. The outer vacuum heat insulation chamber 41 covers an outer
peripheral side (outer side) of the superconducting coil 22 wound
on the stator 20 and held thereby and an outer peripheral side
(outer side) of the stator 20. The inner vacuum heat insulation
chamber 42 covers an inner peripheral side (inner side) of the
superconducting coil 22 and an inner peripheral side (inner side)
of the stator 20. The vacuum heat insulation chamber 40 is
maintained in a high vacuum state (i.e., in a state to be
decompressed relative to an atmospheric pressure) upon shipment.
The vacuum heat insulation chamber 40 is desirably maintained in
the high vacuum state over a long period of time.
Because the superconducting coil 22 is covered by both the outer
vacuum heat insulation chamber 41 and the inner vacuum heat
insulation chamber 42, the superconducting coil 22 is maintained in
an extremely low temperature state, and further in a
superconducting state. As illustrated in FIG. 1, the outer vacuum
heat insulation chamber 41 includes a first insulation chamber
portion 41a covering an outer peripheral portion of the stator 20
and a second insulation chamber portion 41c covering outer
peripheral portions of the conductive portion 33 and the cold head
32. The second insulation chamber portion 41c covers the conductive
portion 33 and the cold head 32 to thereby maintain them at a low
temperature.
As illustrated in FIG. 1, the container 4 includes a first
container 43, a second container 44, a third container 45, and a
fourth container 46 in order from a radially outer side to a
radially inner side. The first to fourth containers 43 to 46 are
coaxially arranged with one another. The first container 43 and the
second container 44 face each other in a radial direction of the
stator core 21 so as to define the outer vacuum heat insulation
chamber 41. The third container 45 and the fourth container 46 face
each other in the radial direction of the stator core 21 so as to
define the inner vacuum heat insulation chamber 42.
The rotor 27 is rotatably arranged in a void 47 having a
cylindrical shape defined by the fourth container 46. The void 47
is connected to an outer atmosphere. The rotor 27 is connected to a
rotating operation member, which is a wheel, for example, in a case
where the superconducting motor device 1 is mounted on a vehicle
such as an automobile. In such case, when the rotor 27 rotates, the
wheel rotates accordingly.
As illustrated in FIG. 1, the first container 43 includes a first
cover portion 431, a guide portion 433, a second cover portion 434,
and an attachment flange portion 435. The first cover portion 431
having a cylindrical shape covers an outer peripheral portion of
the superconducting motor 2. The guide portion 433 defines a guide
chamber 432 for guiding three-phase electric current lead-in wires
56 (which will be hereinafter referred to as lead-in wires 56) that
supply an electric power to the superconducting coil 22. The second
cover portion 434 covers the cold head 32 and the conductive
portion 33. A flange 30c of a compression mechanism 30a that
compresses a refrigerant gas in the refrigerator 30 is mounted on
the attachment flange portion 435. The guide portion 433 is formed,
projecting from the first cover portion 431 that covers the
superconducting motor 2. An outer side of the first container 43
may be exposed to the outer atmosphere but not limited thereto. The
outer side of the first container 43 may be covered by an
insulation material.
The first container 43 is made of a material desirably having a
strength and through which leakage flux does not penetrate or is
difficult to penetrate. A nonmagnetic metal having a low
permeability such as an alloy steel, i.e., an austenitic stainless
steel, is used for the material of the first container 43, for
example. Each of the second, third, and fourth containers 44, 45,
and 46 is made of a material desirably having a high electric
resistance so that a magnetic flux may penetrate through the
second, third and fourth containers 44, 45, and 46 but so as to
restrain eddy current that may be generated on the basis of change
in magnetic flux. A nonmetallic material such as resin, reinforced
resin for a reinforcing material, and ceramics is used for the
material forming the second to fourth containers 44, 45 and 46. The
reinforcing material is a mineral material such as glass and
ceramics, for example. The reinforcing material is desirably a
reinforced fiber and is an inorganic fiber such as a glass fiber
and a ceramic fiber. The resin may be either a thermosetting resin
or a thermoplastic resin.
As illustrated in FIG. 1, a fixed board 70 serving as a first
holding portion is fixed to an upper end of the guide portion 433
that has a cylindrical shape and that projects from a portion of
the first container 43. The fixed board 70 is made of a material
having a high heat insulation and/or difficulty in permeation of
leakage flux. For example, a nonmetallic material such as a
fiber-reinforced resin (reinforced resin for reinforcing material),
resin, and ceramics may be used for the material forming the fixed
board 70. A nonmagnetic metallic material having a low permeability
may be used for the material as the need may be. In such case, an
electric insulation structure is desirably applied to each of the
lead-in terminals 5.
The guide chamber 432 is connected to the outer vacuum heat
insulation chamber 41. Thus, in a case where the superconducting
motor 2 is driven, the guide chamber 432 is in the vacuum
insulation state (i.e., decompressed heat insulation state). The
guide chamber 432 exercises the heat insulation function to thereby
maintain the lead-in terminals 5 at the low temperature.
As illustrated in FIG. 1, the multiple (three) lead-in terminals 5
are electrically connected to the superconducting coil 22 via the
respective lead-in wires 56. The lead-in terminals 5 include a
conductive material as a main material through which an electric
power is supplied to the superconducting coil 22. The lead-in
terminals 5 are fixedly arranged at the fixed board 70 provided at
the end of the guide portion 433 of the first container 43.
A structure for fixing the lead-in terminals 5 to the fixed board
70 is not specifically determined. According to the present
embodiment, as illustrated in FIG. 2, the lead-in terminals 5 are
coaxially inserted into respective first through-holes 71 formed at
the fixed board 70. A seal member 72 is disposed between an inner
wall surface of each of the first through-holes 71 and an outer
wall surface of each of the lead-in terminals 5 so as to increase
air tightness therebetween. Accordingly, the guide chamber 432 is
sealed relative to the outer atmosphere outside of the container 4.
The high vacuum state (decompressed state) of the guide chamber 432
is maintained. As illustrated in FIG. 2, first ends of the lead-in
terminals 5 are accommodated within the guide chamber 432 while
second ends (i.e., male portions 85 to be explained later) of the
lead-in terminals 5 are positioned so as to protrude out of the
guide chamber 432.
The feed terminals 6 are each made of a conductive material as a
base material connected to an external electric power source. In a
case where the superconducting motor 2 is driven, the feed
terminals 6 and the lead-in terminals 5 are electrically connected
to each other so that the electric power is supplied from the feed
terminals 6 to the lead-in terminals 5. Then, the superconducting
coil 22 is powered, thereby generating the rotational magnetic
field (magnetic field).
Materials forming the feed terminals 6 and the lead-in terminals 5
are not specifically defined as long as the materials are
conductive. For example, copper, copper alloy, aluminum, aluminum
alloy, iron, iron alloy, silver, or silver alloy may be used for
the materials forming the feed terminals 6 and the lead-in
terminals 5.
As illustrated in FIG. 1, a current converter 101 and a change-over
switch 66 are provided between an external electric power source
100 and the feed terminals 6. The change-over switch 66 switches
the electric current to be connected or disconnected between the
external electric power source 100 and the feed terminals 6. A
relay switch, a micro switch, a semiconductor switch, or the like
is used as the change-over switch 66. However, in a case where the
external electric power source 100 is an AC power source, the
current converter 101 and the change-over switch 66 may be omitted
so that the feed terminals 6 and the external electric power source
100 are directly electrically connected to each other.
As illustrated in FIG. 2, a heat penetration preventing element 7
(movable connecting device) includes a movable board 74 (movable
member), an extending cylinder 78, and a thermally insulated
chamber 79. The movable board 74 serves as a second holding portion
holding the feed terminals 6. The extending cylinder 78 serves as a
distance adjusting portion for adjusting a distance La between the
movable board 74 and the fixed board 70. The thermally insulated
chamber 79 is formed into a hollow shape of which volume is
changeable because of its accordion structure. The extending
cylinder 78 includes an extensible accordion structure 77. The
extending cylinder 78 may include a flexible structure. As
illustrated in FIG. 2, connection portions between the feed
terminals 6 and the lead-in terminals 5 (i.e., female portions 80
and the male portions 85) are accommodated within the thermally
insulated chamber 79. The movable board 74 is desirably made of a
material having high heat insulation. For example, a nonmetallic
material such as a fiber-reinforced resin (reinforced resin for
reinforcing material), resin, and ceramics may be used for the
material of the movable board 74. Further, metallic material such
as austenitic alloy steel may be used, for example. However the
material of the movable board 74 is not limited thereto.
Because the thermally insulated chamber 79 is maintained in the
high vacuum state, the heat transfer by means of conduction and
convection is restrained. At this time, it is also desirable to
restrain radiation. In a case where the movable board 74 and the
fixed board 70 are made of a metallic material, a heat radiation is
effectively restrained. In a case where the movable board 74 and
the fixed board 70 are made of a nonmetallic material, in order to
restrain heat intrusion or penetration by heat radiation, it is
desirable to provide a metallic layer such as a metallic thin film
and a metallic tape at facing surfaces of the movable board 74 and
the fixed board 70. A metallic material has lower emissivity and
absorption of radiation than a nonmetallic material. However, the
movable board 74 and the fixed board 70 are not limited to have
such structures.
As illustrated in FIG. 2, the fixed board 70 includes multiple or
single connection passages 70a. The guide chamber 432 in the high
vacuum state and the thermally insulated chamber 79 are connected
to each other via the connection passages 70a. Accordingly, an
inside of the thermally insulated chamber 79 is maintained in the
high vacuum state (decompressed state). That is, the thermally
insulated chamber 79 serves as the vacuum heat insulation chamber
(decompressed heat insulation chamber). As illustrated in FIG. 2,
the feed terminals 6 are substantially coaxially inserted into
multiple second through-holes 73 formed at the movable board 74.
The seal member 72 is arranged between an outer wall surface of
each of the feed terminals 6 and an inner wall surface of each of
the second through-holes 73. Therefore, the thermally insulated
chamber 79 is sealed relative to an outer atmosphere, thereby
maintaining the thermally insulated chamber 79 in the high vacuum
state. The seal member 72 desirably includes the high electric
insulation. For example, ceramic seal, rubber seal, or resin seal
is applied to the seal member 72.
According to the present embodiment, the extending cylinder 78
(extending portion) that functions as the distance adjusting
portion between the fixed board 70 and the movable board 74 expands
in an arrow direction Y1 (expansion direction) and contracts in an
arrow direction Y2 (contraction direction). In a case where the
extending cylinder 78 expands in the arrow direction Y1, the fixed
board 70 and the movable board 74 are separated from each other,
thereby increasing the distance La between the fixed board 70 and
the movable board 74. The feed terminals 6 of the movable board 74
are mechanically separated from the lead-in terminals 5 fixed to
the fixed board 70. As a result, the lead-in terminals 5 of the
fixed board 70 and the feed terminals 6 of the movable board 74 are
electrically and thermally separated from each other within the
thermally insulated chamber 79.
The movable board 74 is connected to an actuator 9, for example.
When the actuator 9 is driven, the extending cylinder 78 expands in
the arrow direction Y1 or contracts in the arrow direction Y2. When
the extending cylinder 78 expands in the arrow direction Y1 by the
actuator 9, the fixed board 70 and the movable board 74 are
separated from each other. The feed terminals 6 of the movable
board 74 are mechanically separated from the lead-in terminals 5
fixed to the fixed board 70 within the thermally insulated chamber
79. As a result, the lead-in terminals 5 of the fixed board 70 and
the feed terminals 6 of the movable board 74 are thermally
separated from each other within the thermally insulated chamber
79.
A hydraulic, pneumatic, or electric type actuator, for example, is
applied to the actuator 9. Specifically, a hydraulic cylinder
device, a pneumatic cylinder device, an electric cylinder device, a
hydraulic motor device, a pneumatic motor device, or an electric
motor device is applied to the actuator 9. In a case where the
actuator 9 is a linearly operating type, the driving of the
actuator 9 is directly or indirectly transmitted to the movable
board 74. In a case where the actuator 9 is a rotatably operating
type, a rotational operation of the actuator 9 is converted to a
linear operation by a conversion mechanism and is directly or
indirectly transmitted as the linear operation to the movable board
74.
According to the present embodiment, as illustrated in FIGS. 2 and
3, the female portions 80 serving as engagement bores are formed at
front surfaces of the respective shaft-shaped feed terminals 6
facing the lead-in terminals 5. On the other hand, the male
portions 85 serving as engagement projections are formed at front
surfaces of the respective shaft-shaped lead-in terminals 5 facing
the feed terminals 6. Each of the male portions 85 includes an
axial center 85m. Each of the female portions 80 includes an axial
center 80f. In view of engagement performance, the axial center 85m
of the male portion 85 and the axial center 80f of the female
portion 80 are desirably coaxial with each other.
The male portion 85 and the female portion 80, facing each other,
are engageable with each other. Cross-sectional shapes of the
female portion 80 and the male portion 85 are appropriately
selected to be each formed in a circular shape including a true
circle and an ellipse, a square shape, a quadrangular shape, a
hexagonal shape, and the like. A spring member 88 (see FIG. 2)
serving as an elastic member formed by a conductive material is
disposed between the inner wall surface of the female portion 80
and the outer wall surface of the male portion 85. The spring
member 88 is desirably held by the inner wall surface of the female
portion 80. Alternatively, the spring member 88 may be held by the
outer wall surface of the male portion 85.
The spring member 88 improves an electric contact between the inner
wall surface of each of the female portions 80 and the outer wall
surface of each of the male portions 85 in a state where the male
portion 85 and the female portion 80 engage with each other. The
spring member 88 is elastically deformable in a direction
perpendicular to the axial center 85m of the male portion 85. The
spring member 88 is desirably a leaf spring but may be a coil
spring or a coned disc spring as the need may be.
The conductive material forming the spring member 88 may be copper,
copper alloy, aluminum, aluminum alloy, iron, iron alloy, silver,
silver alloy, and the like. In a case where the electric contact
between the female portion 80 and the male portion 85 is secured,
the spring member 88 disposed between the female portion 80 and the
male portion 85 may be omitted.
According to the present embodiment, when the superconducting motor
2 is driven, the movable board 74 moves in the arrow direction Y2
to approach the fixed board 70 by means of the actuator 9 as
illustrated in FIG. 3. As a result, the male portions 85 of the
lead-in terminals 5 of the fixed board 70 and the female portions
80 of the feed terminals 6 of the movable board 74 engage with each
other and thus make electrically contact with each other within the
thermally insulated chamber 79. At this time, the thermally
insulated chamber 79 is maintained in the high vacuum state
(decompressed state) so as to have high heat insulating properties
relative to outside air. Thus, because of the superconducting coil
22 maintained in the extremely low temperature, the inside of the
thermally insulated chamber 79 is at a low temperature. As a
result, the electric resistance of each of the lead-in terminals 5
and the feed terminals 6 is reduced compared to a case where the
thermally insulated chamber 79 is at a normal temperature. Even in
a case where the Joule heat is generated because of power supply,
the lead-in terminals 5 and the feed terminals 6 are prevented from
being heated. The reduction of electric resistance of each of the
lead-in terminals 5 and the feed terminals 6 is effectively
obtained. Further, because the thermally insulated chamber 79 is in
the high vacuum state, gas inside of the thermally insulated
chamber 79 is prevented from turning to deformation resistance,
thereby effectively maintaining a shrinkage deformation of the
extending cylinder 78.
When the change-over switch 66 is turned on in the aforementioned
state, the three-phase alternating current is supplied from the
feed terminals 6 connected to the external electric power source
100 to the lead-in terminals 5 and further to the superconducting
coil 22. Then, the rotational magnetic field is generated around
the axial center P1 of the superconducting motor 2 to thereby
rotate the rotor 27 about the rotational center P1. The
superconducting motor 2 is driven accordingly. The magnetic flux
penetrates through the third container 45, the inner vacuum heat
insulation chamber 42, and the fourth container 46, thereby
generating an attraction force and a repelling force at the
permanent magnet portions 29 of the rotor 27. The rotor 27 rotates
accordingly.
When the superconducting motor 2 is driven, the superconducting
coil 22 and the stator core 21 are maintained in the extremely low
temperature that is generated by the extremely low temperature
generating portion 3. Thus, the superconducting state of the
superconducting coil 22 is excellently maintained, which leads to
an excellent rotational driving of the superconducting motor 2.
Because the electric resistance of the superconducting coil 22 is
equal to zero or extremely low, the output of the superconducting
motor 2 is high.
When the driving of the superconducting motor 2 is stopped, the
change-over switch 66 is turned off. The movable board 74 of the
heat penetration preventing element 7 moves in the arrow direction
Y1 by the actuator 9 so as to be away from the fixed board 70.
Thus, the multiple feed terminals 6 of the movable board 74
linearly move along the respective axial centers 80f. Consequently,
the lead-in terminals 5 of the fixed board 70 and the feed
terminals 6 of the movable board 74 are electrically separated from
each other within the thermally insulated chamber 79 in the high
vacuum state. The lead-in terminals 5 of the fixed board 70 and the
feed terminals 6 of the movable board 74 are disconnected from each
other.
In such state, as illustrated in FIG. 2, the lead-in terminals 5 of
the fixed board 70 and the feed terminals 6 of the movable board 74
are thermally separated from each other within the thermally
insulated chamber 79. Thus, when the driving of the superconducting
motor 2 is stopped, a heat penetration or intrusion to the lead-in
terminals 5 from the feed terminals 6, which is connected to the
external electric power source 100, is effectively prevented. That
is, a heat transmission path from the feed terminals 6 to the
lead-in terminals 5 within the thermally insulated chamber 79 is
effectively blocked. As a result, when the driving of the
superconducting motor 2 is stopped, heating of the superconducting
coil 22 is prevented, which helps the extremely low temperature
state and the superconducting state of the superconducting coil 22
be maintained. When the superconducting motor 2 is again driven,
the output of the low temperature of the refrigerator 30 is
minimized. The refrigerator 30 can be thus downsized, which leads
to a downsizing of the entire superconducting motor device 1 which
is appropriately mounted on the vehicle.
According to the present embodiment, the thermally insulated
chamber 79 is maintained in the high vacuum state to thereby
restrain heat conduction and heat convection by gas within the
thermally insulated chamber 79. Further, heat conduction and heat
convection by means of the feed terminals 6 connected to the
external electric power source 100 are restrained. In a case where
the feed terminals 6 connected to the external electric power
source 100 and the lead-in terminals 5 facing the feed terminals 6
are each made of metal, emission of radiation from the feed
terminals 6 is prevented while absorption of radiation by the
lead-in terminals 5 is prevented because a metallic material has
lower emissivity and absorption of radiation than a nonmetallic
material. As a result, when the driving of the superconducting
motor 2 is stopped, the heating of the superconducting coil 22 is
further prevented.
According to the present embodiment, as clearly understood from
FIG. 1, the movable board 74 is provided away from the outer vacuum
heat insulation chamber 41 (which is positioned at a low
temperature side) relative to the fixed board 70. That is, the
fixed board 70 is positioned close to the outer vacuum heat
insulation chamber 41 relative to the movable board 74. The lead-in
terminals 5 are held by the fixed board 70 while the feed terminals
6 are held by the movable board 74. Therefore, the feed terminals 6
closed to the external atmosphere are likely to be at a higher
temperature than the lead-in terminals 5. In a case where the
lead-in terminals 5 and the feed terminals 6 are formed by
materials having the same linear expansion coefficients, an inner
diameter the female portion 80 (i.e., the engagement bore) of each
of the feed terminals 6 positioned at a relatively high temperature
side is likely to be expanded. In such case, the engagement
tolerance between the lead-in terminals 5 and the feed terminals 6
increases. The electrical contact between the lead-in terminals 5
and the feed terminals 6 is easily secured by means of the spring
members 88. Alternatively, the lead-in terminals 5 and the feed
terminals 6 may be formed by materials having the different linear
expansion coefficients from each other.
A second embodiment will be explained with reference to FIGS. 4 and
5. The second embodiment basically includes the same structures and
effects as those according to the first embodiment. The second
embodiment includes a cylinder device 90 (a direct driven actuator)
serving as an actuator, specifically, fluid pressure equipment
pneumatically or hydraulically operated, for example. The cylinder
device 90 includes a cylinder body 91 fixed to the movable board 74
and a cylinder rod 92 fixed to the fixed board 70. In a case where
the driving of the superconducting motor device 1 is stopped, a
compressor 93 serving as a fluid supply source is driven by a
control unit 140. Then, a fluid (air is desirable but a liquid such
as oil is acceptable) is supplied to the cylinder body 91 by means
of a control valve 94, thereby bringing the cylinder rod 92 to
extend in an arrow direction Y3. The movable board 74 moves in the
arrow direction Y1 so as to be separated from the fixed board 70.
The lead-in terminals 5 of the fixed board 70 and the feed
terminals 6 of the movable board 74 are disconnected from each
other, which results in the mechanical non-contacting state between
the lead-in terminals 5 and the feed terminals 6. Consequently, the
lead-in terminals 5 and the feed terminals 6 are thermally
separated from each other within the thermally insulated chamber 79
in the high vacuum state.
On the other hand, in a case where the superconducting motor device
1 is driven, the control valve 94 is operated by the control unit
140. The fluid is discharged from the cylinder body 91 so that the
cylinder rod 92 is compressed in an arrow direction Y4. The movable
board 74 moves in the arrow direction Y2 to approach the fixed
board 70. As a result, the lead-in terminals 5 of the fixed board
70 and the feed terminals 6 of the movable board 74 make contact
with each other to be electrically in contact with each other
within the thermally insulated chamber 79 in the high vacuum state.
In such state, the superconducting coil 22 is powered from the
external electric power source 100 via the feed terminals 6 and the
lead-in terminals 5. The single or multiple cylinder device(s) 90
may be provided according to the present embodiment. When the
multiple cylinder devices 90 are provided, the cylinder devices 90
are arranged, having intervals, at an outer side of the lead-in
terminals 5 and the feed terminals 6 (for example, an outer side of
the thermally insulated chamber 79). The cylinder devices 90 are
desirably arranged at equal spaces.
The cylinder device 90 is not limited to have a structure shown in
FIGS. 4 and 5. The cylinder device 90 may include a cylinder body
fixed to the fixed board 70 and a cylinder rod fixed to the movable
board 74.
A third embodiment will be explained with reference to FIG. 6. The
third embodiment basically includes the same structures and effects
as those according to the first and second embodiments. The third
embodiment includes a drive motor 96 (a rotating actuator) fixed to
the fixed board 70 and serving as the actuator operated
electrically or by means of a fluid pressure. A rack portion 97
having a tooth portion 97a is fixed to the movable board 74. A
pinion 98 formed at a motor shaft of the drive motor 96 is meshed
with the rack portion 97. The pinion 98 and the rack portion 97
serve as a conversion mechanism that converts a rotational
operation of the motor shaft of the drive motor 96 into a linear
operation.
When the driving of the superconducting motor device 1 is stopped,
the pinion 98 mounted on the motor shaft of the drive motor 96
rotates in one direction about an axial center P5 of the pinion 98.
The rack portion 97 and the movable board 74 move in the arrow
direction Y1 so as to be separated from the fixed board 70. The
lead-in terminals 5 of the fixed board 70 and the feed terminals 6
of the movable board 74 are disconnected from each other and are
mechanically separated from each other. Consequently, the lead-in
terminals 5 and the feed terminals 6 are thermally separated from
each other.
On the other hand, when the superconducting motor device 1 is
driven, the pinion 98 mounted on the motor shaft of the drive motor
96 rotates in the other direction about the axial center P5. The
movable board 74 then moves in the arrow direction Y2 so as to
approach the fixed board 70. The lead-in terminals 5 of the fixed
board 70 and the feed terminals 6 of the movable board 74 make
contact with each other and are electrically connected to each
other. In such state, the superconducting coil 22 is powered by the
external electric power source via the feed terminals 6 and the
lead-in terminals 5. The single or multiple drive motor(s) 96 may
be provided according to the present embodiment. When the multiple
drive motors 96 are provided, the drive motors 96 are arranged,
having intervals, at an outer side of the lead-in terminals 5 and
the feed terminals 6 (for example, an outer side of the thermally
insulated chamber 79). The drive motors 96 are desirably arranged
at equal spaces.
According to the third embodiment, as illustrated in FIG. 6 a guide
mechanism 99 is provided for improving an engagement guide
performance between the lead-in terminals 5 and the feed terminals
6. The guide mechanism 99 includes a guide shaft 99a and a guide
body 99c. The guide shaft 99a is mounted on the movable board 74
and serves as a guiding portion. The guide body 99c that includes a
guide bore 99b is mounted on the fixed board 70 and serves as a
guided portion. When the feed terminals 6 and the lead-in terminals
5 are mechanically separated from each other, the guide shaft 99a
engages with the guide bore 99b, which exercises a guide function.
Because the guide mechanism 99 is arranged within the thermally
insulated chamber 79, the guide function is prevented from
decreasing because of grit, dust, and the like.
Even when the movable board 74 has high free displacement
characteristics because of the accordion structure 77, the
engagement between the lead-in terminals 5 and the feed terminals 6
is enhanced by means of the guide function of the guide mechanism
99. While the movable board 74 is approaching the fixed board 70,
the guide shaft 99a is further inserted into the guide bore 99b so
as to penetrate through a through-hole 70x formed at the fixed
board 70. The guide mechanism 99 may be also applicable to all
embodiments.
The guide mechanism 99 is provided at the thermally insulated
chamber 79 that functions as the vacuum heat insulation chamber.
Alternatively, the guide mechanism 99 may be provided outside of
the thermally insulated chamber 79. The single or multiple guide
mechanism(s) 99 may be provided according to the present
embodiment. As the need may be, a guide shaft may be mounted on the
fixed board 70 while a guide member including a guide bore may be
mounted on the movable board 74.
A fourth embodiment will be explained with reference to FIG. 7. The
fourth embodiment basically includes the same structures and
effects as those according to the first embodiment. The fourth
embodiment includes protrusion-shaped male portions 85c formed at
respective surfaces of the feed terminals 6 facing the lead-in
terminals 5. In addition, concave-shaped female portions 80C are
formed at respective surfaces of the feed terminals 6 facing the
lead-in terminals 5. The male portions 85C and the female portions
80C face to engage with each other, respectively.
As illustrated in FIG. 7, the movable board 74 is arranged away
from the outer vacuum heat insulation chamber 41 relative to the
fixed board 70. That is, the movable board 74 is positioned close
to the external atmosphere and is likely to be heated compared to
the fixed board 70. The feed terminals 6 are held by the movable
board 74. On the other hand, the lead-in terminals 5 are held by
the fixed board 70 and thus are likely to be at a lower temperature
than the feed terminals 6. Therefore, in a case where the lead-in
terminals 5 and the feed terminals 6 are formed by materials having
the same linear expansion coefficients, respective diameters of the
female portions 80C (i.e., the engagement bores) of the lead-in
terminals 5 are prevented from expanding that may be caused by the
heat expansion. In such case, when the lead-in terminals 5 and the
feed terminals 6 engage with each other, a contact state between
the lead-in terminals 5 and the feed terminals 6 is enhanced. The
lead-in terminals 5 and the feed terminals 6 may be formed by
materials having the different linear expansion coefficients from
each other.
A fifth embodiment will be explained with reference to FIG. 8. The
fifth embodiment basically includes the same structures and effects
as those according to the first to fourth embodiments. According to
the fifth embodiment, the spring member 88 that improves the
electrical contact between the inner wall surface of the female
portion 80 of each of the feed terminals 6 and the outer wall
surface of the male portion 85 of each of the lead-in terminals 5
is eliminated. As illustrated in FIG. 8, the inner wall surface of
each of the female portions 80 forms an inclined surface 80s having
a conical surface shape so that an inner diameter of the inner wall
surface is expanding towards an opening end of the female portion
80. The outer wall surface of each of the male portions 85 forms an
inclined surface 85s having a conical surface shape so that an
outer diameter of the outer wall surface is decreasing towards a
tip end of the male portion 85. According to the aforementioned
structure, the engagement between the female portions 80 and the
male portions 85 is secured. Inclined angles of the inclined
surfaces 80s and 85s relative to the axial centers 80f and 85m,
respectively, are substantially the same.
As illustrated in FIG. 8, the feed terminals 6 are substantially
coaxially inserted into the multiple second through-holes 73 formed
at a movable board 74H having a high electric insulation. A seal
member 72H made of high polymer material such as rubber and resin
that are easily elastically deformable is arranged between the
outer wall surface of each of the feed terminals 6 and an inner
wall surface of each of the second through-holes 73. Accordingly,
the thermally insulated chamber 79 is sealed relative to the
external atmosphere. Because the seal member 72H is elastically
deformable, the female portions 80 of the feed terminals 6 are each
deformed in a radial direction thereof (i.e., an arrow direction
D1) when the female portions 80 of the feed terminals 6 and the
male portions 85 of the lead-in terminals 5 engage with each other,
thereby improving the engagement tolerance between the feed
terminals 6 and the lead-in terminals 5. As the need may be,
however, the seal member 72H may be made of ceramics of which
elastic deformability rather decreases.
A sixth embodiment will be explained with reference to FIG. 9. The
sixth embodiment basically includes the same structures and effects
as those according to the first to fifth embodiments. According to
the sixth embodiment, the vacuum heat insulation chamber 40 and the
guide chamber 432 of the container 4 are each in the high vacuum
state but the thermally insulated chamber 79 is not in the high
vacuum state and is in an atmospheric pressure state or in a state
close thereto. That is, the degree of vacuum of the thermally
insulated chamber 79 is lower than that of the vacuum heat
insulation chamber 40 and the guide chamber 432 of the container 4.
For example, single or multiple air connection bore(s) 74x is
formed at the movable board 74. Accordingly, because the degree of
vacuum of the thermally insulated chamber 79 decreases, a
generation of vacuum discharge between the lead-in terminals 5 and
the feed terminals 6 is prevented when the male portions 85 of the
lead-in terminals 5 and the female portions 80 of the feed
terminals 6 are electrically connected or disconnected.
A seventh embodiment will be explained with reference to FIG. 10.
The seventh embodiment basically includes the same structures and
effects as those according to the first to sixth embodiments.
According to the seventh embodiment, the vacuum heat insulation
chamber 40 is connected to a vacuum pump 40p to thereby maintain
the vacuum heat insulation chamber 40 in the high vacuum state.
Accordingly, the heat insulation of the vacuum heat insulation
chamber 40 relative to the superconducting coil 2 is secured for a
long period of time, which leads to an excellent superconducting
state of the superconducting coil 2.
An eighth embodiment will be explained with reference to FIG. 11.
The eighth embodiment basically includes the same structures and
effects as those according to the first to seventh embodiments. As
illustrated in FIG. 11, the guide portion 433 having a cylindrical
shape and defining the guide chamber 432 is formed at the second
cover portion 434 that covers the cold head 32 of the extremely low
temperature generating portion 3 in the first container 43. The
fixed board 70 serving as the first holding portion is fixed to an
end of the guide portion 433. The lead-in terminals 5 are held by
the fixed board 70. The guide chamber 432 is in the vacuum heat
insulation state (decompressed heat insulation state) as being
connected to the outer vacuum heat insulation chamber 41. Further,
the guide chamber 432 is likely to be maintained at the low
temperature because of the cold head 32 provided close to the guide
chamber 432. Thus, the lead-in terminals 5 held by the fixed board
70 are likely to be maintained at the low temperature.
As illustrated in FIG. 11, the heat penetration preventing element
7 includes the movable board 74, the extending cylinder 78, and the
thermally insulated chamber 79. The movable board 74 serves as the
second holding portion holding the feed terminals 6. The extending
cylinder 78 serves as the distance adjusting portion for adjusting
a distance between the movable board 74 and the fixed board 70. The
thermally insulated chamber 79 is formed into a hollow shape of
which volume is changeable because of its accordion structure. The
extending cylinder 78 includes the extensible accordion structure
77. The multiple feed terminals 6 are held by the movable board 74
as illustrated in FIG. 11.
According to the aforementioned first to eighth embodiments, the
rotor 27 includes the rotational shaft 28 rotatably supported
around the axial center and the multiple permanent magnet portions
29 arranged at the outer peripheral portion of the rotational shaft
28 having intervals in the peripheral direction. Alternatively, the
permanent magnet portions may be provided at the stator 20 and the
superconducting coil 22 may be provided at the rotor 27.
According to the aforementioned first to eighth embodiments, the
superconducting motor device 1 is mounted on the vehicle.
Alternatively, the superconducting motor device 1 may be used in a
stationary state. In addition, according to the aforementioned
first to eighth embodiments, the rotor 27 serves as the mover
because the superconducting motor device 1 is a rotatably operating
type. Alternatively, the superconducting motor device 1 may be a
directly operating linear motor for directly operating the mover.
In this case, the stator 20 is formed, extending in one direction
to generate a movable magnetic field to thereby directly operate
the mover.
According to the aforementioned first to eighth embodiments, the
rotor 27 includes the permanent magnet portions 29 while the stator
20 includes the stator core 21 and the superconducting coil 22
wound on the stator core 21 and held thereby. Alternatively, the
stator includes the permanent magnet options and the rotor includes
the superconducting coil.
Further, the superconducting apparatus is not limited to the
superconducting motor device 1. For example, the superconducting
apparatus according to the first to eighth embodiments is
applicable to a magnetic field generator including a permeable core
through which a magnetic flux of a superconducting coil is
permeable, the superconducting coil and an extremely low
temperature generating portion for cooling the superconducting coil
so as to generate the magnetic field. The permeable core is an iron
core formed by an iron-based material having a high permeability.
For example, a superconducting sputtering apparatus, a magnetic
resonance imaging device (MRI), a nuclear magnetic resonator (NMR),
or a magnetic shield device is applicable to the magnetic field
generator. In other words, a device or an apparatus including the
superconducting coil and the extremely low temperature generating
portion cooling the superconducting coil is applicable to the
superconducting apparatus. A specific structure or function for one
of the embodiments may be applicable to the other of the
embodiments.
The extremely low temperature generating portion 3 maintains the
superconducting coil 22 at the extremely low temperature so as to
maintain the superconducting coil 22 in the superconducting state.
The extremely low temperature falls within a range equal to or
smaller than a critical temperature at which the superconducting
coil 22 shows the superconducting state. Thus, the temperature
range differs depending on the critical temperature and composition
of the superconducting coil 22. In practice, the temperature range
is desirably equal to or smaller than a liquefaction temperature of
nitrogen gas (77K). However, depending on the composition of the
superconducting coil 22, the temperature range may be equal to or
smaller than 100K, or equal to or smaller than 150K. The extremely
low temperature generating portion may be a refrigerator, a
temperature conductive mechanism transmitting the low temperature
from the refrigerator to the superconducting motor, and the
like.
The container 4 defines the vacuum heat insulation chamber 40 for
thermally insulating the superconducting coil 22. The heat
insulation chamber is desirably the vacuum heat insulation chamber.
The "vacuum" state of the vacuum heat insulation chamber
corresponds to the high vacuum state equal to or smaller than
10.sup.-1 Pa, equal to or smaller than 10.sup.-2 Pa, equal to or
smaller than 10.sup.-5 Pa, and the like. However, the vacuum state
is not limited to the aforementioned state. The vacuum insulation
chamber may be maintained in the vacuum state by means of sealing,
suction by a vacuum pump, and the like.
According to the aforementioned embodiments, in a case where the
driving of the superconducting motor 2 is stopped, the lead-in
terminal 5 and the feed terminal 6 are thermally separated from
each other by means of the heat penetration preventing element 7.
Thus, the penetration of heat is prevented to the lead-in terminal
5 from the feed terminal 6 connected to the external electric power
source 100. As a result, the penetration of external heat to the
superconducting coil 2 is restrained when the driving of the
superconducting apparatus 1 is stopped, thereby restraining heating
of the superconducting coil 22.
According to the aforementioned embodiments, the magnetic field
generating portion includes the superconducting motor 2 having the
stator 20 and the rotor 27 which is movable relative to the stator
20, and the superconducting coil 22 is provided at one of the
stator 20 and the rotor 27.
In addition, according to the aforementioned embodiments, the
container 4 includes the fixed board 70 holding the lead-in
terminal 5 and the heat penetration preventing element 7 includes
the movable board 74 holding the feed terminal 6 and the extending
cylinder 78 adjusting a distance between the fixed board 70 and the
movable board 74, the extending cylinder 78 separating the fixed
board 70 and the movable board 74 from each other to mechanically
separate the feed terminal 6 held by the movable board 74 from the
lead-in terminal 5 held by the fixed board 70, the lead-in terminal
5 and the feed terminal 6 being thermally separated from each
other.
Further, according to the aforementioned embodiments, the heat
insulation chamber of the container 4 includes the vacuum heat
insulation chamber 40, and the heat penetration preventing element
7 is maintained in a vacuum heat insulation state while being
connected to the vacuum heat insulation chamber 40, the heat
penetration preventing element 7 including the thermally insulated
chamber 79 having a hollow shape in which the lead-in terminal 5
and the feed terminal 6 are electrically connected to each other in
a case where the superconducting motor 2 is driven.
Furthermore, one of the lead-in terminal and the feed terminal
includes the female portion 80, 80C and the other one of the
lead-in terminal and the feed terminal includes the male portion
85, 85C engageable with the female portion 80, 80C.
Furthermore, the superconducting apparatus includes the elastic
member 88 disposed between the female portion 80, 80C and the male
portion 85, 85C and being elastically deformable, the elastic
member 88 being formed by a conductive material to improve an
electric contact between the female portion 80, 80C and the male
portion 85, 85C.
The principles, preferred embodiment and mode of operation of the
present invention have been described in the foregoing
specification. However, the invention which is intended to be
protected is not to be construed as limited to the particular
embodiments disclosed. Further, the embodiments described herein
are to be regarded as illustrative rather than restrictive.
Variations and changes may be made by others, and equivalents
employed, without departing from the spirit of the present
invention. Accordingly, it is expressly intended that all such
variations, changes and equivalents which fall within the spirit
and scope of the present invention as defined in the claims, be
embraced thereby.
* * * * *